I'll try and summarise this situation, though it could be long!
I'm in a professional job, middle management. Recently, due to a couple of factors I have had a bit of a career surge and been offered some great and prestigious opportunities with the highest levels of management, which I have quietly embraced.
Over the past week I have been told by a couple of sources that my line manager has been talking damagingly about me behind my back, worst of all to my own team, but to others too.
There is one opportunity I've been given that I think is the biggest factor in this - I thought as much when it was presented to me but there was no way I was turning it down so I asked my line managers boss to inform him and then I went to speak to him about it. He assured me it was all fine. I did not seek out this opportunity (I didn't even know it was a thing!).
I don't know what to do about the situation with my line manager. I can't confront him as that would mean betraying the confidences of people who've spoken to me through concern. I can't go to his boss as they are quite close and it would be a bit like running to the teacher I think. I don't want to involve HR. I can't speak to my mentor as my line manager and he are friendly outside of work. Im desperate to have it out with him but I don't see how I can. It's really getting me down, and aside from that I'm worried he'll badmouth me to someone who matters who doesn't know me and they will take his word as gospel therefore spoiling my reputation and career prospects. I've asked the people who've spoken to me not to tell me any more, but I have encouraged them to challenge any talk of this nature in the future.
Any advice?